Cut-out for electric heaters.



PATENTED SEPT. 12. 1905.

J. HRDBN. GUT-OUT PoR BLBGTRIG HBATERS.

APPLIOLTION PELE!) DBO,1,1904.

. UNITED STATES PATENT OFFICE.

JOHANNES HRDEN, OF SCHENECTADY, NET YORK, ASSIGNOR TO GEN- ERAL ELECTRICCOMPANY, A CORPORATION OF NEIV YORK.

CUT-OUT FOR ELECTRIC HEATERS.

Specification of Letters Patent.

Patented Sept. 12, 1905.

Application filed December 1,1904. Serial Nol 235,037.

T0 all whom t may concern:

Beit known that LJOHANNES HRDmasubject of the King of Sweden and Norway,residing at Schenectady, county of Schenectady, State of New York, haveinvented certain new and usefulImprovements in Cut-Outs for ElectricHeaters, of which the following is a specilication.

This invention relates to the improvement of electric heaters.

It has more particularly for its object the improvement of means forcontrolling the heater and the provision of safety mechanism therefor.

While the use of my invention is not restricted as to the receptacle norto the form or particular character of heater to be used therewith, Ilind that it is particularly well adapted for use in connection with aliquidcontaining vessel heated by means of an electric current. It iswell known that vessels of this character are oftentimes ruined bycarelessly allowing the liquid to get so low that the vessel and heatingapparatus are destroyed by excessive heat. This is particularly the casewhen the type of heating unit is one which eX- tends upward from thebottom, a type which is well adapted for rapid heating. My inventionovercomes this dilliculty by providing means for cutting off the currentwhen the liquid falls below a predetermined point in the vessel.

In the drawings is illustrated one method of carrying out my invention,while the scope thereof is defined by the claims appended to and forminga part of this specification.

In the drawings, Figure 1 is a sectional elevation of a heating deviceequipped with my invention. Fig. 2 is a detail of thecircuitinterrupter, and Fig. 3 is a section taken on line 3 3 of Fig. 1looking in the direction of the arrows.

Referring to the drawings, 1 indicates a fluidcontaining receptacle,preferably of metal, and which is heated by means of the edge-wound coil2, constituting a heating unit, the terminal wires of which pass throughthe handle of the vessel 3, which thereby serves as a conduit.

4 is the base of the receptacle and supports it by means of thetelescoping legs 5, 6, and 7, respectively, mounted upon the under sideof the receptacle and upon the base. The

telescoping portions of these legs are kept apart by means of springs 8,secured thereto, thus forming a resilient connection between base 4 andreceptacle 1.

9 indicates the upper, and 10 the lower, portion of a double-polecut-out or interrupter, both insulated from their supports, the upperportion being connected into the circuit of the heater, while the lowerforms a bridging contact and is mounted upon the base 4c, as shown. Ihave shown the cut-out as having spring-jaws so shaped that when forcedtogether they will be locked in that position. This is desirable inorder that the cut-out may not be too sensitive to the increase anddecrease of weight within the vessel. However, I do not limit myself tothis particular forni of cut-out, as other forms thereof may besubstituted without departing from the spirit of my invention.

I have shown a heating unit as covered by a metallic casing 11, which isanged to form the bottom of the vessel 13, and at 12 I have shown laprotecting-casing which is secured to the bottom of the vessel and whichrises and falls therewith.

The operation of my device is very simple.

Vhen there is a sufficient quantity of the fluid in the vessel, thecontacts 9 10 will be closed, as shown in Fig. 2, and the heater is thenin operative condition, while if the fluid falls below a predeterminedpoint-say, for instance, the middle of the casing llthe springs 8 forcethe contacts apart and break the circuit. The point at which the liquidin the vessel will open and close the contacts may be varied as desiredby varying the strength of the springs 8 and the shape and strength ofthe springs of the contacts 9 and 10.

What I claim as new, and desire to secure by Letters Patent of theUnited States. is-

1. The combination of a fluid-receptacle, an electric heater therefor,and means controlled by the weight within the receptacle for cutting outsaid heater.

2. The combination of a fluid-receptacle, an electric heater therefor, ameans for making' and breaking the circuit of the same as the height offluid within the receptacle rises above or falls below a predeterminedpoint.

3. The combination of a fluid-receptacle, an electric heater therein,and an automatic cutout for said heater, said cut-out being controlledby the weight of Huid within the receptacle.

IOO

said vessel and said base, and a cut-out oper- I0 ated by theconnecting` means and controlled by the Weight Within the vessel.

In Witness whereof l have hereunto set my hand this 30th day ofNovember, 1904:.

JOHANNES HRDEN.

VVitnesees:

BENJAMIN B. HULL, HELEN OREORD.

